A FROST ADVISORY is in effect for the Northern Tier until 8 am. As overnight lows are expected to fall into the 30s across the Twin Tiers, areas of patchy frost will become possible in the Southern Tier too.

Frost is a thin layer of ice that forms when water vapor in the atmosphere becomes solid. Temperatures at or below 36 degrees are favorable for frost formation. Additionally, frost formation becomes very widespread when temperatures dip below freezing. There are time when overnight lows fall into the mid 30s during the growing season. In these situations, the National Weather Service puts out Advisory Alerts to protect plants.